Unverified Commit ddf67b14 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
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!15644 ata: libata-sff: Ensure that we cannot write outside the allocated buffer 

Merge Pull Request from: @ci-robot 
 
PR sync from: Zheng Qixing <zhengqixing@huawei.com>
https://mailweb.openeuler.org/archives/list/kernel@openeuler.org/message/UXQJHC3OGK6AIRPVWWSM6ARQMRVSIREA/ 
 
https://gitee.com/src-openeuler/kernel/issues/IBPC5G 
 
Link:https://gitee.com/openeuler/kernel/pulls/15644

 

Reviewed-by: default avatarYu Kuai <yukuai3@huawei.com>
Reviewed-by: default avatarZhang Peng <zhangpeng362@huawei.com>
Signed-off-by: default avatarZhang Peng <zhangpeng362@huawei.com>
parents 045e2df9 a3b59ec1

drivers/ata/libata-sff.c

+10 −8
Original line number Diff line number Diff line
@@ -602,7 +602,7 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) 
{

	struct ata_port *ap = qc->ap;

	struct page *page;

	unsigned int offset;

	unsigned int offset, count;



	if (!qc->cursg) {

		qc->curbytes = qc->nbytes;
@@ -618,25 +618,27 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) 
	page = nth_page(page, (offset >> PAGE_SHIFT));

	offset %= PAGE_SIZE;



	trace_ata_sff_pio_transfer_data(qc, offset, qc->sect_size);

	/* don't overrun current sg */

	count = min(qc->cursg->length - qc->cursg_ofs, qc->sect_size);



	trace_ata_sff_pio_transfer_data(qc, offset, count);



	/*

	 * Split the transfer when it splits a page boundary.  Note that the

	 * split still has to be dword aligned like all ATA data transfers.

	 */

	WARN_ON_ONCE(offset % 4);

	if (offset + qc->sect_size > PAGE_SIZE) {

	if (offset + count > PAGE_SIZE) {

		unsigned int split_len = PAGE_SIZE - offset;



		ata_pio_xfer(qc, page, offset, split_len);

		ata_pio_xfer(qc, nth_page(page, 1), 0,

			     qc->sect_size - split_len);

		ata_pio_xfer(qc, nth_page(page, 1), 0, count - split_len);

	} else {

		ata_pio_xfer(qc, page, offset, qc->sect_size);

		ata_pio_xfer(qc, page, offset, count);

	}



	qc->curbytes += qc->sect_size;

	qc->cursg_ofs += qc->sect_size;

	qc->curbytes += count;

	qc->cursg_ofs += count;



	if (qc->cursg_ofs == qc->cursg->length) {

		qc->cursg = sg_next(qc->cursg);